1. Field of the Invention
This invention relates to a method of manufacturing a motor by surrounding magnetic pole pieces of stator cores with wire winding frames of synthetic resin integrally formed with such cores.
2. Prior Art
A method is known for manufacturing a motor, for instance, a conventional permanent magnet type stepping motor, by putting a plurality of cores provided with pole ridges together into a certain number of layers and forming wire winding frames around the pole ridges as an integral part thereof. Similarly, a technique of arranging and rigidly holding terminals around wire winding frames prepared in the manner described above is also known. Such technique is disclosed, for instance, in Japanese Patent Hei No. 2-27909.
Such techniques are, however, accompanied by certain drawbacks. One of the drawbacks is that, when wire winding frames are formed around pole ridges of a plurality of cores as integral parts thereof, the cores should be placed in respective metal molds properly keeping their positional relationship. This involves complicated steps of operation that are very difficult to automate. Besides, pole ridges impose difficult handling problems particularly if very small pole ridges are required since small pole ridges can easily be deformed in the manufacturing process. Moreover, since the therminials for the motor are prepared as a number different parts that should be press fit to wire winding frames, they can accidentally come off to make the motor inoperable and useless.